Chemical fire-extinguishing apparatus.



3. R. HAMILIOAL.

CHEMICAL FIRE EXTINGUISHING APPARATUS.

.APPLICATION FILED JUNE 26,19l4.

Patented Apr. 30, 1918.

J. R. HAMILTON. CHEMICAL FIRE EXTINGUISHING APPARATUS.

APPLICATION FILED iUNE 26.1914.

1 26%39 1 Patented Apr. 30, 1918.

3 SHEE] S-SHEET 2.

IIIlIIIIII/III/IIIIIIIII/IIIIIIIIIIIIIIIIIIIIIIIIIIIIIII WITNESSES J. R. HAMILTON.

CHEMICAL FIRE EXTINGUISHING APPARATUS.

APPLICATION FILED JUNE 26.1914.

mm m a, Patented Apr. 30, 1918.

3 SHEET S-SHEET 3.

JOHN R. HAMILTON, 0F YONKERS, NEW YORK, ASSIG-NOR T0 SYPI-IO-CHEMIGAL SPRINKLER CORPORATION, .OF CROTON-ON-HUDSON, NEW YORK, A. CORPO- NATION OF N EW YORK.

CHEMICAL FIRE-EXTINGUISHING APPARATUS.

manner.

1 Specification of Letters Patent.

Patented Apr. 3 0, Tfiih.

Application tied an. as, 1914. Serial No. 847,370.

closed under emergency conditions and connected with the chemical mixing tank or other supply tank charged with extinguishing liquid preferably containing carbonate material. Cooperating chemical mixing means are arranged-in connection with the tank and may comprise a siphon or other actuating device to be operated on the emergency condition of the system as by a suction connection with the upper portion thereof so as to operate the mixing means and render effective a predetermined charge of one of the chemicals so as to cause a predetermined working pressure in the chemical tank sufficient to discharge the same from the distributing system on the fire for example. The action of this primary chemical mixing means may be made more efiective by more quickly causing the mixture of chemicals which causes this initial Working pressure and for this purpose the charge of chemical may first be delivered into a receiver from which it may be quickly discharged into the mixing tank as by the automatic discharging action of the receiver, for example. Suitable supplemental mixing means or other pressure generating arrangements may be brought into action and automatically regulated to maintain the predetermined initial Working pressure substantially constant throughout the subsequent operation of the apparatus so that the extinguishing liquid is more effectively discharged at the point of danger.

In the accompanying drawings showing in a somewhat diagrammatic way a number of illustrative embodiments of this invention, I

Figure 1 shows in vertical section one arrangement comprising .a tipping chemical container.

Fig. 2 shows another embodiment.

Fig. 3 shows still a further modification.

Figs. 4.- to 7 are similar sectional views showing still other illustrative arrangements.

The distributing system may be of any desired construct-ion and may as indicated comprise one or more risers or supply pipes 2 to which may be connected various distributing devices such as automatic sprinkler heads orhose connections which may as usual be located at different parts of the building to be protected. The distributing system may be of the wet pipe variety and normally filled with water or other aqueous extinguishing liquid,'such for instance, as a suitable solution of soluble and substantially inert salts to reduce the ,freezing point of the liquid for low temperature Work which should preferably be so selected as to be substantially inert or neutral to the other extinguishing liquid employed in connection with the system. The distributing system may be substantially closed at its upper end as by the cap 3 which may have the reduced venting aperture 4: there-. in of pin-hole size which may furthermore be automatically closed by a check valve 104 or the like under emergency conditions, if desired. The riser or supply pipe may be connected with the supply of extinguishing liquid 1 in any suitable way and may as indicated have its lower portion extend a considerable distance into the carbonate or other extinguishing liquid 17 in this tank so as to extend adjacent the bottom thereof.

The mixing devices used in this connection may comprise any suitable automatically operated mixing means which are tainer. Normally, however, the container is releasably held in the ineffective normal position illustrated by any suitable means, such as the lip 11, on the container with which the actuating stem 8 may cooperate so as to normally hold the container in this position, while when the stem is withdrawn its emergency tipping action can take place. For this purpose a suitable actuating diaphragm such as 7, may be connected to the stem and arranged within a suitable casing or diaphragm chamber 6 which may be connected as by the suction connection 5 with the closed upper part of the distributing system and preferably normally filled with extinguishing liquid so as to give a trouble indication in case any leakage or breakage occurs in this suction actuating connection. The container preferably comprises a primary chemical or acid chamber to contain either one of the chemicals which generate the working pressure in the system and a predetermined charge 13 of this acid or other chemical is placed in this primary chamber so as to generate the desired predetermined initial working pressure when these mixing means operate on the tipping of the container. Under emergency conditions therefore the container quickly overturns and this initial charge of acid quickly acts on the carbonate liquor in the mixing tank 1 so as to generate the desired working pressure of 50 to 100 pounds more or less per square inch and deliver the extinguishing liquid at this high pressure from any operating part of the system. .This pressure is also communicated through its discharge pipe or connection 14 to the air space Within the supplemental chemical or acid chamber in which a supplemental and preferably larger supply of acid or other chemical 16 is arranged. Under these emergency conditions the container is in its overturned position so as to be inverted as compared to what is shown in Fig. 1 and the air or other gaseous medium in the upper part of this supplemental chamber is compressed to substantially the working pressure within the mixing tank. Thereafter the feeding of this chemical component becomes automatic and discharge from the supplemental chamber takes place whenever the pressure in the main mixing tank containing it falls appreciably so that enough acid is then discharged by the greater pressure within the container to increase the pressure in the mixing tank by the resultant chemical action and cause a recompression of the fluid in the container. In this way, the pre determined working pressure can be kept substantially constant throughout the discharge of the extinguishing liquid from the mixing tank provided the different chemicals are present in sufiicient amounts.

Another arrangement is shown in. Fig. 2

as comprising an automatically discharging tipping multiple container or receiver 22 which may as indicated be mounted on a pivot or pin 36 and be provided with a suitable counterweight 38 on the arm 37. This counterweight normally holds the container in the full line position indicated, this normal position being determined by the stop 30 with which the container engages. A charge of pressure producing chemical agent, such as 17, may be arranged in the mixing tank or chemical supply tank 1 con nected to the distributing system in any desired way and a predetermined charge of the cooperating chemical or acid may be poured into the primary chamber or compartment 2 -3 of the tipping receiver so as to mainly stay therein, the surplus acid beyond the lower part of the discharge hole or aperture 101 running into the secondary compartment or chamber 26 so that these two parts 24, 25 of this initial charge of acid, for instance, are automatically proportioned between the two compartments, the greater amount being in the primary compartment as illustrated. Any suitable actuating device which may include a siphon may be used to operate these chemical mixing devices and the siphon 27 may have its short leg 28 dipping into the primary compartment. of the receiver so that when operated it is adapted to transfer part. or all of the contents thereof into the secondary compartment 26. This siphon may be actuated by any suitable means on the emergency condition of the system and an actuating connection or pipe may communicate with the upper portion of this siphon and with a suitable diaphragm chamber 33 in which the diaphragm 34 may be arranged so as to be raised when the liquid or other fluid is withdrawn from the top of this diaphragm through the suction actuating connection 35 which may, for example, communi aite with the closed upper part of the distributing system as previously described. Under these conditions when the system comes into emergency operation as by the opening of one or more of the automatic sprinkler heads the diaphragm is quickly drawn up, drawing up chemical into both legs of the siphon so that the siphon is started and thereafter rapidly transfers the chemical 24; into the secondary con'ipartment 26 of the receiver. This transferring action continues until the turning moment of the receiver is increased sutliciently to overcome the action of the counterweight and the entire receiver then quickly swings around its pivot into the dotted position shown in Fig. 2 in which the heavy counterweight rests against the stop 31. This movement. causes the entire initial charge of chemical to be automatically discharged from the receiver so as to exert the desired pressure generating action meager in the mixing tank and create the initial working pressure in the tank which has been determined upon. This pressure may be subsequently maintained as by the automatic delivery of similar pressure generating acid or other chemical from the supplemental chemical chamber 18 having a discharge connection or pipe 19 so that portions of the in this case may comprise the discharge de vice or passage 41 having its receiving throat 48 adjacent the bottom of the primary chemical chamber so as to discharge substantially all of the acid orother chemical 51 initially placed therein in predetermined amount. This action may be initiated by the suction connection or pipe 45 connected to the upper part of the distributing system as indicated, preferably above the level of the extinguishing liquid in the system where a wet pipe system is used. The emergency operation of the system causes a suction or pressure reduction in this actuating connection so as to reduce the pressure in the receiver or chamber 42 and thus efiect the discharge of the chemical 51 into this receiver, this action being promoted by the equalizing aperture 44 by which this primary chamber is placed in communication with the outside air. This chemical as soon as it accumulates in the receiver to a substantial extent and preferably when practically all of this initial charge of chemical has entered the receiver and the suction is broken in the throat 48 forces open the pivoted or otherwise mounted check valve 46 so as to allow the passage of this predetermined charge of chemical through the discharge throat 47 into contact with the coiiperating chemical 17 which may be a solution of sodium bicarbonate or other carbonate liquid when sulfuric or other acid is used in the primary chamber. In this case the supplemental chemical chamber 49 may be filled with the desired amount of similar acid or chemical 50 to that contained in the primary chamber and may be automatically discharged at intervals through the discharge connection or passage 52, 53 having its lower end 54 extending toward the bottom of the chamber so as to discharge substantially all of the chemical therefrom. The initial mixing in this way of substantially the predetermined amount of acid or other chemical causes the desired initial working pressure within the mixing tanlc in the manner described and this pressure may be subsequently maintained substantially constant throughout the subserpient discharge of extinguishing liquid from the mixing tank.

In the arrangement shown in Fig. 4 the initial charge of acid or other chemical 51 is shown as arranged in the primary chemical or acid chamber 56 preferably adjacent the top of the mixing tank 1. The siphon discharge device or pipe ()0 may cocperate with this primary chamber and have its discharge end (32 provided with a suitable check valve 63 to normally close the same. The suction actuating connection 61 with this siphon effects the starting thereof under emergency conditions of the system by drawing up the acid or other chemical which tends to rapidly pass down the lower part of the siphon so as to open the check valve .more certainly because of itsimpact action and then discharge this chemical into themoperating pressure producing chemical 17 in the mixing tank. It is in some cases desirable to arrange a suitable automatic closing device such as float valve 55 in this suction connection to automatically close the same in case any liquid rises in thepipe which is preferably made of relatively small cross-section to minimize the amount of liquid which it can accommodate. In this way the desired initial workingpressure is caused in the mixing tank and may be subsequently maintained by the automatic discharge of acid or other chemical 50 from the supplemental chemical or acid chamber 57 through the discharge connection 58 which as indicated may extend adjacent the bottom of the chamber.

In the arrangement shown in Fig. 5 the primary chemical or acid chamber 65 may be formed in the upper part of the casing 64 supported in any desired way in the mixing tank 1. The initial charge of acid or other pressure producing chemical 51 may be placed in this chamber and Withdrawn therefrom at the proper time by any suitable actuating arrangement such as the actuating suction connection 69 communicating with the upper part of the distributing system or other means for creating a suction as previously indicated. On the emergency operation of the system the suction caused in this connection draws the acid 51 up into the siphon 68 so as to start the siphon action thereof, the acid or other chemical flowing down through the lower leg of the siphon and opening the check valve 71 so as to continuously discharge the acid into the automatically discharging tipping receiver 70. If desired a suitable equalizer aperture, such as 119, may be formed in the upper part of the primary chamber so as to equalize the air pressure therein. Vvhen this suction action has taken place to such extentthat the desired charge of acid or other chemical has been delivered into the receiver the weight of this acid overbalances the counterweight 73 normally engaging the support 74 and swings the receiver and counterweight about the pivot 7 5 on which they are mounted. This movement carries the parts quickly around into the dotted position indicated. the predetermined charge of acid in the receiver being quickly delivered and mixed with the cooperating chemical 17 in the mixing tank and the check valve 71 being, if desired. positively closed at the same time by a closing device 72 which may be provided on the counterweight to engage and shut the check valve. In this way the initial pressure in the mixing tank may be quickly brought up to substantially a predetermined pressure and may be thereafter maintained at substantially that amount by the intermittent feeding of acid or other chemical from the supplementary chemical chamber 66. the acid 50 or other chemical therein being intermittentlv delivered through the discharge connection 07 in the manner described.

In the arrangement shown somewhat diagrammatically in Fig. 6 the initial charge of acid or the like may be poured into the primary chemical or acid chamber 79 so that part of this charge 51 is contained therein and part passes through the throat 120 and over the partition 121 in this container 76 so as to form the lower portion 83 of this charge within the lower portion of the receiver 77. Under emergency conditions a suction or partial vacuum is caused in any desired way in the suction pipe 78 preferably of relatively small capacity which thus reduces the pressure within the receiver 7 7 and sucks up the charge of acid 51 so that it flows over the partition 121 into this receiver, the trapped lower portion 83 of this charge being simultaneously sucked up somewhat to correspond with the amount of suction exerted. This discharge of the portion 51 of the acid or other chemical may be promoted by-the equalizing connection 80 communicating with the top of this primary chamber 79 and having an automatically opening check valve 81 controlling its inlet end 82. Under these conditions the check valve opens and air enters the primary chamber 79 so that the discharge of acid therefrom continues until the level of the acid reaches the throat 120 whereupon air passes therethrough in sufficient quantities to reduce or break the vacuum in the receiver 77 which allows the comparatively rapid descent of the chemical therein which also promotes this ingress of air through the throat 120. The result is that the larger part of this charge of acid which is then in the receiver 77 is quickly discharged there from into the mixing tank 1 so as to generate pressure therein in connection with the cooperating chemical or carbonate liquor .17. In this way the desired initial working pressure is created in the mixing tank to discharge the extinguishing liquid therefrom and this working pressure may. be subsequently maintained substantially constant by the automatic discharge of the acid or other chemical 50 from the supplemental chemical chamber 85 through the discharge connection 84 in the manner previously described.

In the arrangement shown in the Fig, 7 the primary chemical .or acid chamber 100 may be formed within the casing 86 secured in any desired manner to he mixing tank 1 for instance. The actuating suction connection 87 may communicate with the discharge passage 89 arranged in this chamber or siphon discharging feeder through opening 90 of relatively small area as compared to the area of the discharge pipe 91 leading into the receiver 94 below. This automatically discharging receiver may be provided with an automatically discharging siphon device comprising the discharge connection or conduit 93 and the coi'ipcrating siphon passage 92 substantially concentric therewith, if desired. Under emergency conditions therefore the pressure in the discharge passage 89 is quickly reduced and the initial charge of acid or other chemical 50 is therefore drawn up into thi'spassage so that it can be discharged through the pipe 91 into the receiver below the capacity of the primary chamber 100 being made sullicient to allow for the discharge of this material and preferably tl'is siphon discharging action is promoted by a suitable equalizing venting passage 98 of small area which may be formed in this chamber and automatically closed when desirable by a check valve such as 118 of any suitable description. This action continues until the acid has accumulated in the receiver 94 to such an extent as to rise within the siphon connection up to the top of the discharge pipe 93 thereof which is preferably given such area as to then start the siphon discharge of this acid or other chemical into the cooperating carbonate or other chemical component; 17 below, this siphon discharge action being continued until the entire predetermined charge of pressure producing chemical has become effective, this action takingplace quickly and uninterruptedly because of the large area equalizing aperture 95 which may be formed in the upper part of this receiver. In this way the desired initial working pressure may be rapidly secured in the mixing tank and this may close the suction connection as by closing an automatic ball check valve or the like 88 arranged therein. The initial working pressure thus caused may be subsequently maintained automatically by the automatic feeding into the mixing tank of additional amounts of acid or other chemical 51 from the supplemental chemical chamber 96 which may be arranged in any way to cooperate with the mixing tank and be provided with a siphon discharge connection 97, for instance, extendin toward the bottom of the-chamber an arranged to automatically discharge the liquid therefrom when necessary to maintain the working pressure substantially constant as previously described. I

It is of considerable advantage to supply a measured charge of sulfuric acid or other stable acid in this way to the mixing tank since the desired initial working pressure can be thus secured more certainly and definitely than when the sodium bicarbonate solution or other carbonate material is what is used for the initial measured charge. lit is also desirable to use suitable means to maintain substantially constant the effective strength of the acid that is to prevent its carbonate generating action belng decreased by dilution or other causes WhlCll often become of serious importance after the apparatus has been charged for months. For this purpose it is desirableto cover the surface of the acid where it is exposed to the arr or to the gaseous medium within the mixing tank or other parts of the apparatus with a thin film or layer-of inert mineral oil or other impervious material 131 which may of course be considerably thinner than is in- "dicated in Fig, 7, capable of preventing substantial absorption of moisture. For similar reasons it is also desirable to have the acid containers formed or lined with material such as 132 which is substantially inert to the action of acid of the strength employed. Such protecting oil films or layers may therefore be applied to the upper surface of the acid 50 within the acid chamber 100 and within the discharge passage 89 around the central discharge pipe. For similar reasons it is also desirable to use similar means to maintain the effective strength of the acid substantially constant in the other forms of apparatus described, although moderate moisture absorption is not so important in such forms'of the apparatus as render effective the entire charge of acid originally placed in the primary acid chamber or container as shown in Figs. 1, 2 and so forth.

This invention has been described in connection with a number of illustrative embodiments, parts, materials, and arrangements, to the details of which disclosure the invention is not of course to be limited, since what is claimed as new and what is desired to be secured by Letters Patent is set forth in the appended claims:

1. In fire extinguishing apparatus, a wet pipe distributing system having an upper portion substantially closed under emergency conditions, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing meanscomprising a siphon and a suction actuating connection therefor communicating with the upper portion of said distributing system and operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixing tank and automatically operating chemical mixing means comprising a chamber having an at least substantially closed top and a siphon discharge connection extending adjacent the bottom of said chamber and communicating -with said tank to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

2. In fire extinguishing apparatus, a wet pipe distributing system, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid if thereto, chemical mixing means comprising a siphon and an actuating connection therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge to be'operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause apredetermined Working pressure in said mixing tank and automatically operating chemical mixing means comprising a chamber having an at least substantially closed top and a discharge connection extending adjacent the bottom of said chamber and communicating with said tank to maintain the predetermined working pres-. sure substantially constant throughout the discharge of the extinguishing liquid from said tank. I

3. In fire extinguishing apparatus, a distributing system, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating connection therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predeterminedworking pressure in said mixing tank and automatically operating chemical mixing means to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

4. In -fire extinguishing apparatus, a wet pipe distributing system having an upper portion substantially closed under emergency conditions, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor communicating with the upper portion of said distributing system and operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixing tank and means automatically operating to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

5. In fire extinguishing apparatus, a wet pipe distributing system, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixingtank and means automatically operating to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing iiquid from said tank. I

6. In fire extinguishing apparatus, a wet pipe distributing system, a chemical mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided With an automatically starting discharge to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixing tank and means automatically operating to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

7. In fire extinguishing apparatus, a distributing system, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixin tank..

8. In fire extinguishing apparatus, a distributing system, a chemical mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting siphon discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixing tank.

9. In fire extinguishing apparatus, a distributing system, a chemical mixing tank a connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixing tank.

10. In fire extinguishing apparatus, a wet pipe distributing system having an upper portion substantially closed under emergency conditions, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising chemical feeder and a suction actuating device therefor communicating with the upper portion of said distributing system and operated on the emergency condition of said distributing system to start said feeder, a receiver into which said feeder discharges and provided with an automatically starting siphon discharge device to be operated when a prede-l30 termined charge has entered said receiver and discharge the same therefrom to cause a predetermined working pressure in said mixing tank and automatically operating chemical mixing means comprising a chamber having an at least substantially closed top and a discharge connection extending adjacent the bottom of said chamber and communicating with said tank to malntaln the stantlally constant throughout the discharge of the extinguishing liquid from said tank.

11. In fire extinguishing apparatus, a distributing system, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising achemical feeder and a suction actuating device therefor operated on the emergency condition of said distributing system to start said feeder, a receiver into which said feeder discharges and provided with an automatically starting siphon discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined Working pressure in said mixing tank and automatically operating chemical mixing means comprising a chamber having a substantially closed top and a discharge connection extending adjacent the bottom of said chamber and communicating with saidv tank to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

12. In fire extinguishing apparatus, a distributing system, a chemical mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a chemical feeder and a suction actuating device therefor operated on the emergency condition of said distributing system to start said feeder, a receiver into which said feeder discharges and provided with an automatically starting siphon discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermined working,

pressure in said mixing tank and automati cally operating chemical mixing means comprising a chamber to maintain the predetermined. working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

13. In fire extinguishing apparatus, a distributing system, a chemical mixing tank connedted to said distributing! system to supply extinguishing liquid thereto, chemical mixing means comprising a chemical feeder and a suction actuating device therefor operated on the emergency condition of said distributing system to start said redetermined working pressure sub feeder, a receiver into which said. feeder discharges and provided with an automatically starting discharge device to be operate d when a predetermined charge has entered said recelver and discharge the same therefrom to cause a working pressure in said mixing tank and automatically operating chemical mixing means comprislng a chamber to maintain the predetermined Working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

14. In fire extinguishing apparatus, a distributing system, a chemical mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a chemical feeder and a suction actuating device therefor operated on the emergency condition of said distributing system to start said feeder, a receiver into Wluch said feeder discharges and provided with an automatically starting siphon discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a predetermlned working pressure in said mixing tank.

15. In fire extinguishing a paratus, a distributing system, a chemica mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a chemical feeder and a suction actuating device therefor operated on the emergency condition of said distributing system to start said feeder, a, receiver into which said feeder discharges and provided with an automatically starting discharge device to be operated when a predetermined charge has entered said receiver and discharge the same therefrom to cause a working pressure in said mixing tank.

16. In fire extinguishing apparatus, a Wet pipe distributing system having an upper portion substantially closed under emergency conditions, a chemical mixing tank charged with carbonate extinguishing liquid and connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and a suction actuating device therefor communicating with the upper portion of said distributing system to start said siphon tion extending adjacent the bottom of said chamber and communicating with said tank to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

17. In fire extinguishing apparatus,'a wet pipe distributing system having an upper portion substantially closed under emergency conditions, a chemical mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and a suction actuating device therefor communicating with the upper portion of said distributing system to start said siphon under emergency conditions and render effective a predetermined charge of one of the chemicals and cause a working pressure in said mixing tank and automatically operating chemical mixing means to maintain the predetermined workingpressure substantially constant throughout the discharge of the extinguishing liquid from said tank.

18. In fire extinguishing apparatus, a wet pipe distributing system, a chemical mixing tank connected to said distributing system to supply extinguishing liquid thereto, chemical mixing means comprising a siphon and an actuating device therefor communieating with said distributing system to start said siphon under emergency conditions and render effective a predetermined charge of one of the chemicals and cause a working pressure in said mixing tank and aut0mati-.

cally operating chemical mixing means to maintain the predetermined working pressure substantially constant throughout the discharge of the extinguishing liquid from said tank. 19. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extinguishing liquid, an acid chamber charged with sulfuric acid, means to prevent variation in the effective strength of said acid by moisture absorption, cooperating acid feeding means comprising a siphon operated on the emergency condition of said system to discharge a predetermined charge of said acid into said tank and create the initial working pressure in said tank and automatic means comprising an acid chamber having a substantially closed top and a siphon discharge connection extending toward the bottom of said chamber and communicating with said tank to maintain said working pressure in said tank during the withdrawal of liquid therefrom.

20. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extinguishing liquid, an acid chamber charged with sulfuric acid, means to prevent variation in the effective strength of said acid, coiiperating acid feeding means comprising a siphon operated 011 the emergency condition of said system to discharge a predetermined charge of said acid into said tank and-create the initial working pressure in said tank and automatic means to maintain said working ressure in said tank during the withdrawal of liquid therefrom.

21. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extinguishin liquid, an acid chamber charged with sulfuric acid, means to prevent variation in the effective strength of said acid, cooperating acid feeding means operated on the emergency condition of said system to discharge a predetermined charge of said acid into said tank and create the initial working pressure in said tank and automatic means to maintain said working pressure in said tank during the withdrawal of liquid therefrom.

22. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extinguishing liquid, an acid chamber charged with sulfuric acid, cooperating acid feeding means operated on the emergency condition of said system to discharge a predetermined charge of said acid into said tank and create the initial working pressure in said tank and automatic means to maintain said working pressure in said tank during the withdrawal of liquid therefrom.

23. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extingnishing liquid, an acid chamber and cooperating chemical mixing means operated on the emergency condition of said system to discharge a predetermined charge of acid of definite effective strength into said -,tank to create the initial working pressure therein and automatic means comprising an acid chamber having a substantially closed top and a siphon discharge connection extending toward the bottom of said chamber and communicating with said tank to maintain said working pressure in saidtank during'the withdrawal of liquid therefrom.

24. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extinguishing liquid, an acid chamber and cooperating chemical mixing means operated on the emergency condition of said system to discharge a predetermined charge of acid into said tank to create the initial working pressure therein and automatic means comprising an acid chamber having an at least substantially closed top and a discharge connection extending toward the bottom of said chamber and comn'mnicating with said tank to maintain said working pressure in said tank during the withdrawal of liquid therefrom.

25. In fire extinguishing apparatus, a distributing system and connected pressure operated supply tank charged with carbonate extinguishing liquid, an acid chamber meager and cotiperating chemical mixing means operated on the emergency condition of said system to discharge a predetermined charge of acid into said tank to create the initial working pressure therein and automatic means comprising an acid chamber having an at least substantially closed top to maintain said working pressure in said tank during the withdrawal of liquid therefrom.

26. In fire extinguishing apparatus, a distributing system, a connected chemical mixing tank charged with carbonate extinguishing liquid, chemical means comprising an acid chamber containing a charge of sulfuric acid covered with a protecting layer of inert oily material, a cooperating actuating device operated on the emergency condition of the system to discharge said acid and an automatically starting receiver into which said acid is discharged to automatically discharge a predetermined charge of said acid into said carbonate liquor to cause the initial working pressure in said mixing tank and automatic chemical mixing means to thereafter maintain the working pressure substantially constant,

27. In fire extinguishing apparatus, a dis tributing system, a connected chemical mixing tank charged with carbonate extinguishing liquid, chemical means comprising an acid chamber containing a charge of sulfuric acid covered with a layer of inert protecting material, a cooperating actuating device operated on the emergency condition of the system to discharge a predetermined charge of said acid into said carbonate liquor to cause the initial working pressure in said mixing tank and means to thereafter maintain the working pressure substantially constant.

28. In fire extinguishing apparatus, a distributing system, a chemical mixing tank charged with carbonate liquid and connected to said distributin system to supply extinguishing liquid t ereto, chemical mixing means comprising. an acid chamber, a siphon and an actuating device therefor operated on the emergency condition of said distributing system to start said siphon, a receiver into which said siphon discharges and provided with an automatically starting discharge device to be operated when a predepressure in said termined charge has entered said receiver and discharge the same therefrom to cause the initial Working pressure in said mixing tank.

29. In fire extinguishing apparatus, a dis tributing system, a connected supply tank, cooperating siphon means operating on the emergency condition of said system to cause a predetermined working fiuid pressure in said tank and means to automatically maintain said pressure substantially constant thrpiughout thedischarge of liquid from said tan 30. In fire extinguishing apparatus, a supply of extinguishing liquid, cooperating chemical pressure generating means comprising an acid container containing a predetermined charge of pressure generating chemical to generate a substantially predetermined initial pressure, a protecting layer of inert oily material extending over said chemical to prevent undesirable action of the gaseous medium contained in the upper part of said chamber and supplemental pressure generating means to thereafter maintain the working pressure substantially constant.

31. In fire extinguishing apparatus, chemical pressure generating means comprising a tank containing carbonate extinguishing liquid and a communicating acid chamber having an overflow passage and containing a charge of sulfuric acid and a protecting layer ofinert oily material extending over said acid to prevent undesirable action of the gaseous medium in the upper part of said chamber.

32. In fire extinguishing apparatus, a distributing system, a connected chemical mixing tank charged with carbonate extinguishing liquid, chemical means comprislng a siphon and a cooperating acid chamber containing a charge of acid covered with a layer of inert protecting material, a cooperating actuating device operated on the emergency condition of the system to discharge a predetermined charge of said acid into said carbonate liquor to cause the initial working mixing tank. JOHN R. HAMILTON. Witnesses:

Jnssm 1B. KAY, I-IARRY I1. DUNCAN. 

